#include "sys/container.h"
#include "sys/system.h"

#include "../lib/map.h"

static void rb_insert_color(Node *, Map *);
static Node *rb_next(const Node *);
static Node *rb_first(const Map *);

static void __rb_rotate_left(Node *node, Map *root)
{
	Node *right = node->rb_right;
	Node *parent = rb_parent(node);

	if ((node->rb_right = right->rb_left))
		rb_set_parent(right->rb_left, node);
	right->rb_left = node;

	rb_set_parent(right, parent);

	if (parent)
	{
		if (node == parent->rb_left)
			parent->rb_left = right;
		else
			parent->rb_right = right;
	}
	else
		root->rb_node = right;
	rb_set_parent(node, right);
}

static void __rb_rotate_right(Node *node, Map *root)
{
	Node *left = node->rb_left;
	Node *parent = rb_parent(node);

	if ((node->rb_left = left->rb_right))
		rb_set_parent(left->rb_right, node);
	left->rb_right = node;

	rb_set_parent(left, parent);

	if (parent)
	{
		if (node == parent->rb_right)
			parent->rb_right = left;
		else
			parent->rb_left = left;
	}
	else
		root->rb_node = left;
	rb_set_parent(node, left);
}

void rb_insert_color(Node *node, Map *root)
{
	Node *parent, *gparent;

	while ((parent = rb_parent(node)) && rb_is_red(parent))
	{
		gparent = rb_parent(parent);

		if (parent == gparent->rb_left)
		{
			{
				register Node *uncle = gparent->rb_right;
				if (uncle && rb_is_red(uncle))
				{
					rb_set_black(uncle);
					rb_set_black(parent);
					rb_set_red(gparent);
					node = gparent;
					continue;
				}
			}

			if (parent->rb_right == node)
			{
				register Node *tmp;
				__rb_rotate_left(parent, root);
				tmp = parent;
				parent = node;
				node = tmp;
			}

			rb_set_black(parent);
			rb_set_red(gparent);
			__rb_rotate_right(gparent, root);
		}
		else
		{
			{
				register Node *uncle = gparent->rb_left;
				if (uncle && rb_is_red(uncle))
				{
					rb_set_black(uncle);
					rb_set_black(parent);
					rb_set_red(gparent);
					node = gparent;
					continue;
				}
			}

			if (parent->rb_left == node)
			{
				register Node *tmp;
				__rb_rotate_right(parent, root);
				tmp = parent;
				parent = node;
				node = tmp;
			}

			rb_set_black(parent);
			rb_set_red(gparent);
			__rb_rotate_left(gparent, root);
		}
	}

	rb_set_black(root->rb_node);
}

static void __rb_erase_color(Node *node, Node *parent,
							 Map *root)
{
	Node *other;

	while ((!node || rb_is_black(node)) && node != root->rb_node)
	{
		if (parent->rb_left == node)
		{
			other = parent->rb_right;
			if (rb_is_red(other))
			{
				rb_set_black(other);
				rb_set_red(parent);
				__rb_rotate_left(parent, root);
				other = parent->rb_right;
			}
			if ((!other->rb_left || rb_is_black(other->rb_left)) &&
				(!other->rb_right || rb_is_black(other->rb_right)))
			{
				rb_set_red(other);
				node = parent;
				parent = rb_parent(node);
			}
			else
			{
				if (!other->rb_right || rb_is_black(other->rb_right))
				{
					rb_set_black(other->rb_left);
					rb_set_red(other);
					__rb_rotate_right(other, root);
					other = parent->rb_right;
				}
				rb_set_color(other, rb_color(parent));
				rb_set_black(parent);
				rb_set_black(other->rb_right);
				__rb_rotate_left(parent, root);
				node = root->rb_node;
				break;
			}
		}
		else
		{
			other = parent->rb_left;
			if (rb_is_red(other))
			{
				rb_set_black(other);
				rb_set_red(parent);
				__rb_rotate_right(parent, root);
				other = parent->rb_left;
			}
			if ((!other->rb_left || rb_is_black(other->rb_left)) &&
				(!other->rb_right || rb_is_black(other->rb_right)))
			{
				rb_set_red(other);
				node = parent;
				parent = rb_parent(node);
			}
			else
			{
				if (!other->rb_left || rb_is_black(other->rb_left))
				{
					rb_set_black(other->rb_right);
					rb_set_red(other);
					__rb_rotate_left(other, root);
					other = parent->rb_left;
				}
				rb_set_color(other, rb_color(parent));
				rb_set_black(parent);
				rb_set_black(other->rb_left);
				__rb_rotate_right(parent, root);
				node = root->rb_node;
				break;
			}
		}
	}
	if (node)
		rb_set_black(node);
}

void rb_erase(Node *node, Map *root)
{
	Node *child, *parent;
	int color;

	if (!node->rb_left)
		child = node->rb_right;
	else if (!node->rb_right)
		child = node->rb_left;
	else
	{
		Node *old = node, *left;

		node = node->rb_right;
		while ((left = node->rb_left) != NULL)
			node = left;

		if (rb_parent(old))
		{
			if (rb_parent(old)->rb_left == old)
				rb_parent(old)->rb_left = node;
			else
				rb_parent(old)->rb_right = node;
		}
		else
			root->rb_node = node;

		child = node->rb_right;
		parent = rb_parent(node);
		color = rb_color(node);

		if (parent == old)
		{
			parent = node;
		}
		else
		{
			if (child)
				rb_set_parent(child, parent);
			parent->rb_left = child;

			node->rb_right = old->rb_right;
			rb_set_parent(old->rb_right, node);
		}

		node->rb_parent_color = old->rb_parent_color;
		node->rb_left = old->rb_left;
		rb_set_parent(old->rb_left, node);

		goto color;
	}

	parent = rb_parent(node);
	color = rb_color(node);

	if (child)
		rb_set_parent(child, parent);
	if (parent)
	{
		if (parent->rb_left == node)
			parent->rb_left = child;
		else
			parent->rb_right = child;
	}
	else
		root->rb_node = child;

color:
	if (color == RB_BLACK)
		__rb_erase_color(child, parent, root);
}

static void rb_augment_path(Node *node, rb_augment_f func, void *data)
{
	Node *parent;

up:
	func(node, data);
	parent = rb_parent(node);
	if (!parent)
		return;

	if (node == parent->rb_left && parent->rb_right)
		func(parent->rb_right, data);
	else if (parent->rb_left)
		func(parent->rb_left, data);

	node = parent;
	goto up;
}

/*
 * after inserting @node into the tree, update the tree to account for
 * both the new entry and any damage done by rebalance
 */
void rb_augment_insert(Node *node, rb_augment_f func, void *data)
{
	if (node->rb_left)
		node = node->rb_left;
	else if (node->rb_right)
		node = node->rb_right;

	rb_augment_path(node, func, data);
}

/*
 * before removing the node, find the deepest node on the rebalance path
 * that will still be there after @node gets removed
 */
Node *rb_augment_erase_begin(Node *node)
{
	Node *deepest;

	if (!node->rb_right && !node->rb_left)
		deepest = rb_parent(node);
	else if (!node->rb_right)
		deepest = node->rb_left;
	else if (!node->rb_left)
		deepest = node->rb_right;
	else
	{
		deepest = rb_next(node);
		if (deepest->rb_right)
			deepest = deepest->rb_right;
		else if (rb_parent(deepest) != node)
			deepest = rb_parent(deepest);
	}

	return deepest;
}

/*
 * after removal, update the tree to account for the removed entry
 * and any rebalance damage.
 */
void rb_augment_erase_end(Node *node, rb_augment_f func, void *data)
{
	if (node)
		rb_augment_path(node, func, data);
}

/*
 * This function returns the first node (in sort order) of the tree.
 */
Node *rb_first(const Map *root)
{
	Node *n;

	n = root->rb_node;
	if (!n)
		return NULL;
	while (n->rb_left)
		n = n->rb_left;
	return n;
}

Node *rb_next(const Node *node)
{
	Node *parent;

	if (rb_parent(node) == node)
		return NULL;

	/* If we have a right-hand child, go down and then left as far
	   as we can. */
	if (node->rb_right)
	{
		node = node->rb_right;
		while (node->rb_left)
			node = node->rb_left;
		return (Node *)node;
	}

	/* No right-hand children.  Everything down and left is
	   smaller than us, so any 'next' node must be in the general
	   direction of our parent. Go up the tree; any time the
	   ancestor is a right-hand child of its parent, keep going
	   up. First time it's a left-hand child of its parent, said
	   parent is our 'next' node. */
	while ((parent = rb_parent(node)) && node == parent->rb_right)
		node = parent;

	return parent;
}

void rb_replace_node(Node *victim, Node *new,
					 Map *root)
{
	Node *parent = rb_parent(victim);

	/* Set the surrounding nodes to point to the replacement */
	if (parent)
	{
		if (victim == parent->rb_left)
			parent->rb_left = new;
		else
			parent->rb_right = new;
	}
	else
	{
		root->rb_node = new;
	}
	if (victim->rb_left)
		rb_set_parent(victim->rb_left, new);
	if (victim->rb_right)
		rb_set_parent(victim->rb_right, new);

	/* Copy the pointers/colour from the victim to the replacement */
	*new = *victim;
}

static Pair *getMap(Map *root, char *str)
{
	Node *node = root->rb_node;
	while (node)
	{
		Pair *data = container_of(node, Pair, node);

		//compare between the key with the keys in Pair
		int cmp = strcmp(str, data->key);
		if (cmp < 0)
		{
			node = node->rb_left;
		}
		else if (cmp > 0)
		{
			node = node->rb_right;
		}
		else
		{
			return data;
		}
	}
	return NULL;
}

void *map_get(Map *root, char *key)
{
	Pair *data = getMap(root, key);
	if (data != NULL)
	{
		return data->val;
	}
	return NULL;
}

int map_set(Map *root, char *key, void *val)
{
	Pair *data = (Pair *)kmalloc(sizeof(Pair));
	data->key = (char *)kmalloc((strlen(key) + 1) * sizeof(char));
	strcpy(data->key, key);
	int size = root->size > 0 ? root->size : ((strlen(val) + 1) * sizeof(char));
	data->val = (char *)kmalloc(size);
	memcpy(data->val, val, size);

	Node **new_node = &(root->rb_node), *parent = NULL;

	while (*new_node)
	{
		Pair *this_node = container_of(*new_node, Pair, node);
		int result = strcmp(key, this_node->key);
		parent = *new_node;

		if (result < 0)
		{
			new_node = &((*new_node)->rb_left);
		}
		else if (result > 0)
		{
			new_node = &((*new_node)->rb_right);
		}
		else
		{
			memcpy(this_node->val, val, size);
			kfree(data);
			return 0;
		}
	}
	rb_link_node(&data->node, parent, new_node);
	rb_insert_color(&data->node, root);
	root->length++;
	return 1;
}

static Pair *map_first(Map *tree)
{
	Node *node = rb_first(tree);
	return (rb_entry(node, Pair, node));
}

static Pair *map_next(Node *node)
{
	Node *next = rb_next(node);
	return rb_entry(next, Pair, node);
}

static void map_free(Pair *node)
{
	if (node != NULL)
	{
		if (node->key != NULL)
		{
			kfree(node->key);
			node->key = NULL;
			kfree(node->val);
			node->val = NULL;
		}
		kfree(node);
		node = NULL;
	}
}

int map_remove(Map *tree, char *key)
{
	Pair *data = getMap(tree, key);
	if (data != NULL)
	{
		tree->length--;
		rb_erase(&data->node, tree);
		map_free(data);
		return 1;
	}
	return 0;
}

void *map_keys(Map *tree, void *key)
{
	if (tree->length == 0)
	{
		return NULL;
	}
	Pair *node;
	static Pair *data;
	if (*(char *)key == '\0')
	{
		node = map_first(tree);
		data = node;
	}
	else
	{
		data = map_next(&(data->node));
		if (data == NULL)
		{
			return NULL;
		}
	}
	int size = tree->size > 0 ? tree->size : ((strlen(data->key) + 1) * sizeof(char));
	memcpy(key, data->key, size);
	return data->key;
}

void *map_values(Map *tree, void *val)
{
	if (tree->length == 0)
	{
		return NULL;
	}
	Pair *node;
	static Pair *data;
	if (*(char *)val == '\0')
	{
		node = map_first(tree);
		data = node;
	}
	else
	{
		data = map_next(&(data->node));
		if (data == NULL)
		{
			return NULL;
		}
	}
	int size = tree->size > 0 ? tree->size : ((strlen(data->val) + 1) * sizeof(char));
	memcpy(val, data->val, size);
	return data->val;
}

void map_clear(Map *tree)
{
	char temp[50] = "";
	while (1)
	{
		map_keys(tree, temp);
		if (*temp != '\0')
		{
			map_remove(tree, temp);
			memset(temp, '\0', 50);
			continue;
		}
		else
		{
			break;
		}
	}
}